Alonso was present at F1 pre-season testing earlier this year and became a McLaren ambassador.
His return to test a 2019 vehicle raised questions over his F1 future and when asked by Autosport if the test was about keeping himself sharp for a potential race return, Alonso said: "No".
Alonso will drive on both days, on each occasion at the wheel of an MCL34 McLaren is running to aid Pirelli's tyre development.
But he has switched his post-F1 racing career focus to attempting to complete his triple crown bid with victory at the Indianapolis 500, as well as his Toyota World Endurance Championship campaign.
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I don't think anyone sees it as an extra pressure or anything. "I am so happy to be one match away from defending the title". On the women's side, Barty is finally through to her first Miami Open final after what turned into a six-hour delay.
"As I said past year, and in Barcelona [testing] as well, my idea is not to come back". Coming back is not in the plan.
"I don't close doors 100% to anything in the future".
"Maybe, if I was relaxing at home, it would be different, but I've been testing many different things so much that I've had not time to miss anything".
"On Pirelli it's more about testing the tyres and maybe [I will] have a little bit of an idea of what the auto is doing this year and being involved a little bit from last year in the development in the vehicle is useful for the team so I hope it's a productive test".
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Depuis plusieurs mois, de nombreux clubs s'intéressent en effet à lui, notamment Manchester United ou le Paris Saint-Germain. Rapide, puissant et très bon dans l'anticipation, le joueur sénégalais est une référence à son poste.
"I'm part of the McLaren family and whatever my contribution can help the team I'm happy to do it", he said.
"We have put some solutions in place for this race, and if they will work or not we need to see".
Sainz will also drive on Tuesday morning in the auto McLaren is free to run as it pleases, with team-mate Lando Norris taking over that vehicle on Tuesday afternoon and driving for the entire day on Wednesday.
Asked if he watched the opening round of the F1 season in Australia two weeks ago, Alonso added: "It was good, it was good". That's why I took the decision. "I knew the result so that changed a little bit the perspective, but it was very relaxed".
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Earlier, Mnuchin told reporters that USA officials had a "very productive working dinner" on Thursday. This story has not been edited by Firstpost staff and is generated by auto-feed.